Devices On The Isa Bus; The Super I/O Controller (Ns 82317) - HP P Class 450/500/550/600/650/700/750 Reference Manual

Devices on the ISA Bus

Table 2-9. Devices on the ISA Bus
Ultra I/O

The Super I/O Controller (NS 82317)

The Ultra I/O chip (NS 82317) provides the control for two FDD devices, one serial port
and one bidirectional multi-mode parallel port.
Serial / Parallel Communications Ports
The 9-pin serial ports (whose pin layouts are shown in the section "Socket Pin Layouts for
Minitower Models" in the chapter "Interface Devices and Mass-Storage Drives") supports
RS-232-C and are buffered by 16550A UARTs, with 16-Byte FIFOs. They can be
programmed as COM1, COM2, COM3, COM4, or disabled.
The 25-pin parallel port (also shown in the section "Socket Pin Layouts for Minitower
Models" in the chapter "Interface Devices and Mass-Storage Drives") is Centronics
compatible, supporting IEEE 1284. It can be programmed as LPT1, LPT2, or disabled. It
can operate in the four following modes:
Standard mode (PC/XT, PC/AT, and PS/2 compatible).
Bidirectional mode (PC/XT, PC/AT, and PS/2 compatible).
Enhanced mode (enhanced parallel port, EPP, compatible).
High speed mode (MS/HP extended capabilities port, ECP, compatible).
FDC
The integrated flexible disk controller (FDC) supports any combination of two of the
following: tape drives, 3.5-inch flexible disk drives, 5.25-inch flexible disk drives. It is
software and register compatible with the 82077AA, and 100% IBM compatible. It has an
A and B drive-swapping capability and a non-burst DMA option.
RTC
The real-time clock (RTC) is 146818A-compatible, with an accuracy of 20ppm (parts per
million). The configuration RAM is implemented as 256 bytes of CMOS. The RTC operates
on a 32.768 kHz crystal and a separate 3V lithium battery that provides up to 7 years of
protection.
Keyboard and Mouse Controller
The computer has an 8042-based keyboard and mouse controller. The connector pin
layouts are shown in the section "Socket Pin Layouts for Minitower Models" in the chapter
"Interface Devices and Mass-Storage Drives."
Chapter 2
ISA Device
Devices on the ISA Bus
Index
2Eh
System Board
Data
2Fh
59